Network Working Group X. Li Internet-Draft C. Bao Intended status: Informational CERNET Center/Tsinghua University Expires: April 22, 2010 October 19, 2009 DNS46 for the IPv4/IPv6 Stateless Translator draft-xli-behave-dns46-for-stateless-00 Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on April 22, 2010. Copyright Notice Copyright (c) 2009 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents in effect on the date of publication of this document (http://trustee.ietf.org/license-info). Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Abstract The stateless translator can support IPv6-initiated communications as well as the IPv4 initiated communications for the IPv6 hosts using IPv4-translatable addresses. The DNS support for the IPv6-initiated Li & Bao Expires April 22, 2010 [Page 1] Internet-Draft DNS46 for Stateless Translator October 2009 communication is defined in the DNS64 document. This document defines the DNS46 function for the stateless translator. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Notational Conventions . . . . . . . . . . . . . . . . . . . . 4 3. DNS function for the IPv4/IPv6 Stateless Translator . . . . . . 4 3.1. DNS64 function for the IPv4/IPv6 Stateless Translator . . . 4 3.2. DNS46 function for the IPv4/IPv6 Stateless Translator . . . 4 3.2.1. Fix AAAA record . . . . . . . . . . . . . . . . . . . . 4 3.2.2. Varying AAAA record . . . . . . . . . . . . . . . . . . 5 4. Security Considerations . . . . . . . . . . . . . . . . . . . . 5 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5 6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . 5 7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 5 7.1. Normative References . . . . . . . . . . . . . . . . . . . 5 7.2. Informative References . . . . . . . . . . . . . . . . . . 6 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 6 Li & Bao Expires April 22, 2010 [Page 2] Internet-Draft DNS46 for Stateless Translator October 2009 1. Introduction The IPv4/IPv6 translation framework document [I-D.ietf-behave-v6v4-framework] presents the 8 scenarios and introduces the stateless and stateful operation modes of the IPv4/ IPv6 translators. The stateless translator can support the following scenarios. o Scenario 1: An IPv6 network to the IPv4 Internet. o Scenario 2: The IPv4 Internet to an IPv6 network. o Scenario 5: An IPv6 network to an IPv4 network. o Scenario 6: An IPv4 network to an IPv6 network. The stateful translator can support the following scenarios. o Scenario 1: An IPv6 network to the IPv4 Internet. o Scenario 3: The IPv6 Internet to an IPv4 network. o Scenario 5: An IPv6 network to an IPv4 network. DNS mechanism is one of the functions model for the IPv6/IPv4 transition [I-D.ietf-behave-v6v4-framework]. In general, there are the DNS64 for providing the name/address resolving from IPv4 to IPv6 and the DNS46 for providing the name/address resolving from IPv6 to IPv4. In addition, if the destination is "an IPvX network", it is the authoritative DNS server with IPvX and IPvY entries in the zone file, while if the destination is "the IPvY Internet", it performs the function for synthesizing the IPvX records from the IPvY records [RFC1035]. The DNS64 should support: o Scenario 1: An IPv6 network to the IPv4 Internet (synthesizing). o Scenario 3: The IPv6 Internet to an IPv4 network (authoritative). o Scenario 5: An IPv6 network to an IPv4 network (authoritative). The DNS46 should support: o Scenario 2: The IPv4 Internet to an IPv6 network (authoritative). o Scenario 6: An IPv4 network to an IPv6 network (authoritative). Li & Bao Expires April 22, 2010 [Page 3] Internet-Draft DNS46 for Stateless Translator October 2009 2. Notational Conventions The key words MUST, MUST NOT, REQUIRED, SHALL, SHALL NOT, SHOULD, SHOULD NOT, RECOMMENDED, MAY, and OPTIONAL, when they appear in this document, are to be interpreted as described in [RFC2119]. 3. DNS function for the IPv4/IPv6 Stateless Translator The stateless translator can support IPv6-initiated communications as well as the IPv4 initiated communications for the IPv6 hosts using IPv4-translatable addresses, which requires the DNS64 function, as well as the DNS46 function [I-D.xli-behave-ivi]. o Scenario 1: An IPv6 network to the IPv4 Internet (DNS64, synthesizing). o Scenario 2: The IPv4 Internet to an IPv6 network (DNS46, authoritative). o Scenario 5: An IPv6 network to an IPv4 network (DNS64, authoritative). o Scenario 6: An IPv4 network to an IPv6 network (DNS46, authoritative). 3.1. DNS64 function for the IPv4/IPv6 Stateless Translator The DNS64 function is for Scenarios 1 and Scenario 3, which are also used for the stateful translators. The DNS64 function is defined in DNS64 document [I-D.ietf-behave-dns64]. 3.2. DNS46 function for the IPv4/IPv6 Stateless Translator This document defines the DNS46 function and it is the authoritative DNS server with A and AAAA entries in the zone file. 3.2.1. Fix AAAA record This is very similar to the authoritative DNS configuration of the dual-stack hosts. The only difference is that in the dual-stack case, the A record and AAAA record are independent, while in stateless translation case, the hosts are IPv6 single stack using IPv4-translatable addresses and the A record can be derived from the AAAA record based on the algorithm and the PREFIX information [I-D.ietf-behave-address-format]. Li & Bao Expires April 22, 2010 [Page 4] Internet-Draft DNS46 for Stateless Translator October 2009 3.2.2. Varying AAAA record If IPv6 host has a varying AAAA record (that is, it could change due to the IPv6-only host changing its IPv6 address and registering its new address via, for example, Dynamic DNS), then the dynamic DNS46 function is required. However, it is still the authoritative DNS. The A record can be derived from the AAAA record based on the algorithm and the PREFIX information [I-D.ietf-behave-address-format]. 4. Security Considerations There are no security considerations in this document. 5. IANA Considerations This memo adds no new IANA considerations. Note to RFC Editor: This section will have served its purpose if it correctly tells IANA that no new assignments or registries are required, or if those assignments or registries are created during the RFC publication process. From the author's perspective, it may therefore be removed upon publication as an RFC at the RFC Editor's discretion. 6. Acknowledgments The authors would like to acknowledge the following contributors of this document: Dan Wing and Kevin Yin. 7. References 7.1. Normative References [I-D.ietf-behave-address-format] Huitema, C., Bao, C., Bagnulo, M., Boucadair, M., and X. Li, "IPv6 Addressing of IPv4/IPv6 Translators", draft-ietf-behave-address-format-00 (work in progress), August 2009. [I-D.ietf-behave-dns64] Bagnulo, M., Sullivan, A., Matthews, P., and I. Beijnum, "DNS64: DNS extensions for Network Address Translation from IPv6 Clients to IPv4 Servers", Li & Bao Expires April 22, 2010 [Page 5] Internet-Draft DNS46 for Stateless Translator October 2009 draft-ietf-behave-dns64-00 (work in progress), July 2009. [I-D.ietf-behave-v6v4-framework] Baker, F., Li, X., Bao, C., and K. Yin, "Framework for IPv4/IPv6 Translation", draft-ietf-behave-v6v4-framework-01 (work in progress), September 2009. [RFC1035] Mockapetris, P., "Domain names - implementation and specification", STD 13, RFC 1035, November 1987. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. 7.2. Informative References [I-D.xli-behave-ivi] Li, X., Bao, C., Chen, M., Zhang, H., and J. Wu, "The CERNET IVI Translation Design and Deployment for the IPv4/ IPv6 Coexistence and Transition", draft-xli-behave-ivi-02 (work in progress), June 2009. Authors' Addresses Xing Li CERNET Center/Tsinghua University Room 225, Main Building, Tsinghua University Beijing 100084 CN Phone: +86 10-62785983 Email: xing@cernet.edu.cn Congxiao Bao CERNET Center/Tsinghua University Room 225, Main Building, Tsinghua University Beijing 100084 CN Phone: +86 10-62785983 Email: congxiao@cernet.edu.cn Li & Bao Expires April 22, 2010 [Page 6]